In tippy Eigen, in Visual Studio 2015 I get lots of warnings like these
2>c:\users\belli\documents\code\coolprop-v5-new\externals\eigen\eigen\src/Core/MathFunctionsImpl.h(36): warning C4305: 'argument': truncation from 'double' to 'const float'
The offending lines seem to be of the type:
const T alpha_1 = pset1<T>(4.89352455891786e-03);